Our Blogs

Fermentation and Punching Down the Cap

Posted by CM Support
Oct 1, 2015 | Keywords: fermentation  fermenters  foot crushing  how to make wine  Pinot Noir  red wine  wine  wine technology  winemaker  winemaking  

Once the cold-soak process is complete, the “must” is ready for fermentation. Our fermentation tanks – fermentors –  hold either one-half ton or 1.6 tons of must, and need to be warmed to the point where the bad natural yeasts are avoided and the good natural yeasts can become active, consuming the grapes’ sugar and producing alcohol. The temperature for fermentation peaks at 90-92 degrees Fahrenheit. To initiate fermentation, we circulate warm water through the tank jackets. It takes about two days to warm the must in each tank so that fermentation can begin. 



While the must ferments, we punch down the cap daily. The cap floats on the top of the fermenting wine in each tank; a dense layer of stems, skins and berries, buoyed by CO2 released by the yeast activity. In order to get the most from the cap we have to incorporate it back down into the fermenting wine. Some wineries do this by draining the liquid from the bottom of their tanks and pouring it back over the cap.

At Clos de la Tech, we have adapted the classic approach, using a custom-designed tool to gently break up and submerge the cap.



Breaking through the dense cap, and pushing sections down into the juice allows further extraction of flavor elements and tannins, and is a very serious physical work-out!



The cap is punched down in each tank, vigorously or gently, up to three times a day during fermentation, depending on the results of the spectrophotometric analysis of color and tannin. Along with our meticulous monitoring of temperature, sugar and alcohol, one of the key signs of completed fermentation is that the cap solids start to sink -- so it’s on to our custom-designed press.



We created a press that presses the must gently – the whole tank is placed in the press and raised up slowly pushing the must against a press plate. The must pushes through liquid allowing the liquid to gravity flow through a filter into a hose that goes through the wall of the fermentation cave to the barrel cave and directly into the barrels to begin aging.



Clos de la Tech Pinot Noir is currently available for purchase here.